Bolster and side bearing railway car leveling mechanism

ABSTRACT

A combination bolster, side bearing, and side frame truck levelizer for railroad car trucks in which the truck bolster carries on either side of its center plate structure a side bearing that is of a constant contact type, with each bearing including a bearing plate acting on a body of resilient elastomeric material, in which the bearing plates are connected through a lost motion connection to a scissors lever type linkage assembly linking the side frames and the bolster mid portion, with the arrangement being such that roll tendencies in excess of those absorbed by the side bearings are translated into vertical movement of the bolster by applying to the bolster at its mid portion most of the unbalanced forces involved in such roll tendencies.

D United States Patent 1151 3,653,331 Chierici 1 Apr. 4, 1972 [54] BOLSTER AND SIDE BEARING 3,354,837 11/1967 Williams ..105/197 R RAILWAY CAR LEVELING 3,3556%; Vilgamlsl... MAGS/:37 R NI 9 ,6 8 ar we ...105 7 R MECHA SM 3,518,948 7/1970 King et al.... ..308/l38 X [72] Inventor: Osvaldo F. Chierici, Elmhurst, lll.

Primary ExaminerArthur L. La Point [73] Asslgnee' Holland Company Assistant Examinerl-loward Beltran [22] Filed: Dec. 8, 1969 Attorney-Mann, Brown, McWilliams & Bradway [2|] Appl. No.: 882,864 [57] ABSTRACT A combination bolster, side bearing, and side frame truck [52] R 7 3 g levelizer for railroad car trucks in which the truck bolster car- [511 Int Cl 8815/14 B61f5/24 B6lf17/O4 ties on either side of its center plate structure a side bearing [58] Field of Search ..105/197 R, 199 R, 164, 185, that 9 3 type mclumlg IDS/193 197 D 199 A 200 308/138 a bearmg plate actlng on a body of resillent elastomerlc material, in which the bearing plates are connected through a lost motion connection to a scissors lever type linkage as- [56] References Cited sembly linking the side frames and the bolster mid portion, UNITED STATES PATENTS with the arrangement being such that roll tendencies in excess of those absorbed by the s1de bearings are translated mto ver- 2,301,372 1 1/1942 Cottrell ..308/138 tica] movement f the bolster by applying to the bolster at its llgarraows et la1. mid portion most of the unbalanced forces involved in such r at et a roll tendencies. 3,323,470 6/1967 Williams ....105/197 R 3,329,098 7/1967 Williams 105/197 R 9 Claims, 7 Drawing Figures 52 44 2 O4 64 n0 26 62 A 38 39 12 H2 ,7 11

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4 '04 126A 62 11 A I 2A |2OA 12o 1 34 32/ 122A 7 122 PATENTEDAPR 4 I572 3,653,331

sum 1 OF 2 1O 4 3O 12 22 T 2 INVENTOR OSVALDO F. CHIE RIC] ATTORNEYS PATENTED APR 4 I972 SHEET 2 OF 2 )NVENTOR OSVALDO F. CHIERICI ATTORNEYS BOLSTER AND SIDE BEARING RAILWAY CAR LEVELING MECHANISM This invention relates to a levelizing arrangement for railroad car trucks, and more particularly, to a combination side bearing and levelizing arrangement adapted for association with standard bolsters to adapt same to resist roll tendencies of railroad cars.

As is well known in the art, railroad track rail lengths on each side of the track are spliced together end-to-end in 39 foot lengths, with the joints being staggered on either side of the track. The joints are roughly equally spaced apart longitudinally of the track. Consequently, as a train of cars goes down a track, the tendency of the truck wheels to drop at each joint splice induces a harmonic rock and roll action of the car bodies at speeds of to 22 miles per hour that can build up sufficiently to overturn one or more cars and wreck the train.

Various ways have been proposed to overcome such side sway tendencies. Examples are those involving hydraulic or other types of snubbing arrangements that are suitably activated when excessive roll tendencies develop, and scissors type bolster arrangements in which the truck bolster is of a special multiple lever construction articulated between the truck side frames. Such devices are not considered feasible from a practical railroading standpoint due to high cost and inconsistency of result.

A principal object of this invention is to provide a simple mechanical arrangement for resisting roll tendencies that consistently achieves this end by keeping the bolster substantially level under all vertical loads that may be imposed on it.

Another principal object of the invention is to provide a mechanical type leveling arrangement especially adapted for use in connection with standard bolsters.

Another principal object of the invention is to provide a combination constant contact side bearing and levelizing arrangement for application to railroad car trucks equipped with standard bolsters, in which the side bearings operate independently during normal operation to absorb vertical motion, but when roll harmonics build up, beyond what the side bearings are designed to absorb, the resulting loads are applied to the bolster in a manner that will downwardly deflect opposite ends of the bolster substantially equally and thus oppose tilting motions of the car body being carried by the truck in question.

Other objects of the invention are to provide a truck levelizing arrangement that is readily applicable to existing equipment, to provide an improved side bearing arrangement for railroad cars, and to provide side bearings and levelizing arrangements that are economical of manufacture, convenient to apply, and long lived in use.

In accordance with this invention, the truck bolster is provided with a pair of constant contact side bearings, of which the individual side bearings each comprise a resiliently compressible elastomeric element seated on the bolster, surmounted by a bearing plate that is engaged by the car body bolster, with the bearing plates being arranged to have limited vertical deflecting movement in compression relation to the compressible elements. The bearing plates are connected to, through a lost motion connection arrangement having a lost motion sufficient to allow closure of the bearing plates, a scissors lever linkage arrangement interconnecting the side frames and mid portion of the bolster, such that when roll tendencies exceed that which can be absorbed by the side bearings, the forces involved are transmitted to the bolster in a manner which ensures both ends of same will deflect downwardly substantially equally.

Other objects, uses, and advantages will be obvious or become apparent from a consideration of the following detailed description and the application drawings, in which like reference numerals indicate like parts throughout the several views.

In the drawings:

FIG. I is a side elevational view of a typical railroad car truck that may be equipped with the present invention;

FIG. 2 is a view taken substantially along line 2-2 of FIG. 1, but showing only the bolster, side frames, and spring groupings, illustrating my invention applied thereto, largely in block diagram form, showing the parts under normal load conditions, with the car body bolster cooperating with same shown in outline;

FIG. 3 is a view similar to that of FIG. 2, but showing the operation of my invention when the car body supported by the truck shown in FIGS. 1 and 2 tends to roll to the right of FIG.

FIG. 4 is a plan view of the bolster shown in FIG. 1, showing my invention applied thereto, with the side frames illustrated largely in block diagram form;

' FIG. 5 is a side elevational view of the arrangement shown in FIG. 4;

FIG. 6 is a fragmental cross-sectional view taken substantially along line 6-6 of FIG. 5; and

FIG. 7 is a fragmental cross-sectional view taken substantially along line 77 of FIG. 4.

However, it is to be understood that the specific disclosure provided is supplied primarily to comply with the requirements of the patent code, and that the invention may have other specific embodiments which will be obvious to those skilled in the art.

GENERAL DESCRIPTION Reference numeral 10 generally indicates a typical railroad car truck to which my invention may be applied in association with its bolster 12 and side frames 14 and 16. As is conventional, the side frames 14 and 16 are journalled as at 18 on axles 20 of suitable wheels 22 riding on conventional track rails 24.

The bolster 12 as illustrated is intended to represent any conventional standard bolster, and as is conventional, the ends 26 and 28 of the bolster are received in the window openings 30 of the respective side frames, where they rest on conventional spring groupings 32 made up of a plurality of compression springs 34 that are seated on the base 36 of the side frame window opening.

As indicated in FIGS. 4 and 5, the bolster 12 includes the usual center plate structure 38 for cooperation with a corresponding center plate structure 39 of the railroad car body bolster 41 in the usual and conventional manner. Bolster 12 includes opening 40 that receives the kingpin (not shown) which connects the car body and truck bolsters to form the usual pivot connection between the car body and its trucks.

In accordance with this invention, the truck 10, and specifically its side frames 14 and 16 and bolster 12, are equipped with a combination side bearing and levelizing device 42, which comprises a pair of constant contact side bearings 44 and 46 associated with two sets of levelizing linkages or assemblies 48 and 50, one on either side of the bolster (see FIG. 4). As linkages 48 and 50 are identical, only one is illustrated and described in detail.

The side bearings 44 and 46 each generally comprise a bearing plate 52 that are respectively engaged by suitable seats 53 carried by the body bolster, a receptacle 54, and a resilient elastomeric body 56 seated in the receptacle 54 on which the bearing plate 52 rests. The bearing plate 52 of each bearing unit can be deflected downwardly under compression loads until it engages the upper surface 58 of receptacle 54.

The bearing units each include a pair of strap elements 60 on either side thereof which respectively have a lost motion connection, with the respective levelizing linkages 48 and 50. The connection to linkage 48 is indicated at 62 and 62A, and is with the respective swing arms 64 and 64A of linkage 48 that are swingably connected to the respective side frames and are operably connected to a pair of scissors levers 66 and 68, which are in turn pivoted as at 70 and 72 to the respective side frames, and are swingably connected to the midportion of the truck 12 by lost motion connection 74.

The arrangement is such that during normal operation of the car equipped with the combination device 42, the bolster 12 operates as usual with loadings that are strictly vertical.- Light tendencies to roll will be absorbed by the respective constant contact side bearings 44 and 46 through the compression of their resilient bodies 56, with the side bearings operating independently of the linkages 48 and 50 to the extent permitted by the lost motion connection 62.

When roll tendencies have become severe enough to cause the bearing plates 52 to deflect to the point where the motion provided by lost motion connections 62 has been exceeded, the straps 60 of the bearing unit in question (for instance, the right hand bearing unit 46, as shown in FIG. 3) force the scissors levers 66 and 68 (of linkages 48 and 50) downwardly about their respective pivotal connections 70 and 72 (lever 68 of linkage 48 and lever 66 of linkage 50 where the bearing unit 46 is involved), and thus apply an appropriately downwardly acting force on the bolster at the lost motion connections 74 and on either side of the bolster. As indicated, the lost motion connections 74 are at the midportion or length of the bolster, and consequently the bolster is forced to move uniformly downwardly at both of its ends against the spring action of spring groupings 32, whereby the normal level position of the bolster is maintained. Tendencies to sway in the other direction are handled in the same manner, but by the indicated action of swing lever 64A on scissors lever 66, as will be apparent from FIG. 3.

It will thus be seen that this invention contemplates that light roll tendencies will be overcome by the action of the constant contact side bearings 44 and 46. More severe roll tendencies will be dissipated by conversion of roll action into strictly vertical movement of the bolster.

SPECIFIC DESCRIPTION As indicated, the bolster 12 and side frames 14 may be of any desired type, although it is intended that this invention be specifically applicable to trucks employing the standard AAR bolster or its equivalent.

The side bearings 44 and 46 are identical in design. Receptacles 54 may be affixed to the bolster in any suitable manner, and in the form shown, the bearing unit receptacles 54 each comprise a base plate 80 fixed to the top of the bolster in any suitable manner, as by rivets 81 or by welding, and having affixed thereto, as by welding, side plates 82 and end plates 84, which define a pocket 86 in which the respective resilient bodies 56 are seated.

The upper edges of the plates 84 and 86 are coplanar to define the top surface 58 that limits the vertical deflection of the respective bearing plates 52.

The bodies 56, which may be formed from any suitable resiliently flexible material of suitable load resistance, such as urathane having a durometer of between about 70 to about 90, are shaped to define, for stability purposes, flat upper and lower end surfaces 88 and 90 against which the Hat undersurface 92 of the bearing plate 52 and flat base 94 of the pocket 86, engage. Bodies 56 are of barrel outline in vertical crosssectional configuration, both in the plane of FIG. 7 and in the plane at right angles thereto, and are of rectangular horizontal cross-sectional configuration, with the long dimension thereof extending longitudinally of the bolster.

The bodies 56 may be secured within the respective pockets 86 in any suitable manner, as for instance, by a bolt 95 extending between the respective plates 80 and a recess 97 within the respective bodies 56 for cooperation with the respective nuts -99, or by a suitable bond between the bodies 56 and the respective plates 80.

The bearing plates 52 have fixed thereto across their respective midportions, as by welding, a wear plate 98 against which the body bolster engages.

The respective straps 60 are fixed, as by welding, to the respective ends 100 and 102 of the bearing plates 52 and depend down on either side of the bolster for application to lost motion connections 62 and 62A. Straps 60 are each formed with an elongate slot 104 for this purpose, which slot has a length approximating the permissible vertical deflection or closure travel of the bearing plates 52. The connection between the respective straps 60 and bearing plates 52 may be reinforced by suitable plates 1 1 1 or the like suitably welded in place (see FIG. 7).

The swing lever 64 of linkage 48 comprises a swing arm having one of its ends 112 pivotally connected by pin 113 to a suitable lug 114 that is suitably affixed to the side frame adjacent same, and the other of its ends 116 pivoted as by pin 118 to thrust arm 120 that is in turn connected by pin 122 to the end 124 of scissors lever 68.

A pin 126 fixed to swing arm 110 is received in the slot 104 of the adjacent strap 60.

The swing lever 64A at the other side of the truck is similarly constituted, it comprising swing arm 110A having its end 112A secured by a suitable pin 113A to lug 114A that is appropriately affixed to the side frame 14. End 116A of arm 110A is secured by pin 118A to thrust arm 120A, which in turn is secured by pin 122A to the end 128 of scissors lever 66.

Pin 126A fixedly carried by swing arm 110A is received in the slot 104 of the bearing unit 44 strap 60.

The cross levers 66 and 68 of linkage 48 are similar in nature, the cross lever 66 having its end 130 pivoted to lug 132, 3'

suitably fixed to the side frame 16, by suitable pin 134 that forms connection 70. Similarly, the end 136 of cross lever 68 is pivoted to lug 138, suitably affixed to side frame 14, by pin 140, to form connection 72.

Lost motion connections 74 between the mid portion of bolster 12 and the scissors levers 66 and 68 on either side of the bolster comprises a pin 142 (see FIG. 6) suitably anchored to the bolster 12, as by being fixed between mounting plates 144 and 145 which in turn are suitably welded to the bolster (mounting plate 144 is omitted from FIGS. 2, 3 and 5). Scissors levers 66 and 68 are respectively formed with the elongate slots 146 and 148 through which the pin 142 extends. Slots 146 and 148 extend lengthwise of their respective levers 66 and 68.

As is apparent from a showing of FIG. 4, the levelizing linkage 50 is the same as linkage 48, and consequently a specific description of linkage 48 will suffice also for linkage 50, although it will be apparent that these linkages operate in tandem on either side of the bolster to oppose roll tendencies, and at one end of the bolster, a set of swing arms 64 and 64A and their associated parts are on either side of the bolster, while at the other end of the bolster, the other set of swing arms 64 and 64A and their associated parts are on either side of the bolster. However, the corresponding parts of linkages 48 and 50 are identical and may be used interchangably.

The showing of FIGS. 4-7 illustrates the parts of the invention referred to in a more specific manner over the diagrammatic showing of FIGS. 2 and 3. Similar reference numerals are employed to indicate identical parts throughout all of these views.

It will therefore be seen that this invention defines a simplified mechanical device that will reliably overcome roll tendencies. The constant contact side bearings 44 and 46 act independently of the rest of the device to the extent of their capacity, whereupon they bring into operation the cross lever assemblies 48 and 50 that act in tandem to convert severe roll motions into straight vertical movement of the bolster by applying the vertical forces involved to the midportion of the bolster, as represented by the pins 142.

The result is that the only motion that the bolster makes is straight up and down movement, during roll tendencies, with the result that roll tendencies are overcome.

The foregoing description and the drawings are given merely to explain and illustrate the invention and the invention is not to be limited thereto, except insofar as the appended claims are so limited, since those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

I claim:

1. In a railroad car truck including spaced side frames between which wheeled axles are journalled and, a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement ineluding:

a pair of constant contact resilient side bearing devices carried by the bolster, one on either side of its said midportion,

with one of said devices being disposed adjacent one of said side frames and the other of said devices being disposed adjacent the other of said side frames,

each of said devices including a vertically deflectable member and an elastomeric element interposed between same and said bolster, for resiliently opposing vertical deflection of the respective deflectable members,

and linkage means interconnected between said side frames, said midportion of said bolster, and said side bearings for translating rolling tendencies applied to said side bearings into vertical movement of said bolster achieved through downward forces applied to said bolster at said bolster midportion.

2. In a railroad car truck adapted to support a railroad car body, said truck having first and second side frames in parallel, spaced-apart relation, and a laterally disposed bolster resiliently supported at its respective ends on said side frames, the combination of a resiliently compressible side bearing member secured to said bolster adjacent the first side frame, and including a resiliently supported movable element adapted to support a portion of the weight of the car body, a lever arm having one end thereof connected to said movable element by a vertical motion transmitting linkage and extending from adjacent said movable element to the second side frame and pivotally secured to said second side frame, a second resiliently compressible side bearing and corresponding resiliently supported movable element secured to said bolster adjacent the second side frame, and a second lever arm having one end thereof connected to the second mentioned movable element by a second vertical motion transmitting linkage and extending from adjacent the latter movable element to the first side frame and pivotally secured to said first side frame, and including means for swingably securing said lever arms in scissors-like relation to the midportion of the bolster, said means including means to accommodate free vertical movement of said bolster with respect to said side frames.

3. In a railroad car truck including spaced side frames between which wheeled axles are journalled, and a bolster member extending between and resiliently supported by the respective side frames, said bolster member being formed at its midportion for pivotal connection to a railroad car body, the improvement wherein:

a resiliently flexible side bearing device is mounted on either side of said midportion of said bolster member,

said side bearing devices including a bearing plate seated on a resilient body with said body being proportioned to maintain said bearing plate in constant contact with the car body when the car body is carried by the truck,

a pair of scissors arms swingably connected together and to the bolster at said midportion thereof intermediate their ends, by lost motion connections and having like ends of each swingably secured to the respective side frames and the other ends of each secured through lost motion connection means to the bearing plate of the respective side bearings adjacent same,

said lost motion connection means permitting closure of said side bearing devices on vertical movement of the car body prior to actuating said scissors arms,

whereby on closure of said side bearings said scissors arms are actuated to permit only vertical movement of said bolster member.

4. in a railroad car truck including spaced side frames between which wheeled axles are journalled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including:

a pair of constant contact resilient side bearing devices are carried by the bolster, one on either side of its said midportion,

with one of said devices being disposed adjacent one of said side frames and the other of said devices being disposed adjacent the other of said side frames,

each of said devices including a vertically deflectable member,

a pair of scissors levers swingably connected together and to the bolster at its said midportion,

with like ends of the respective levers being respectively swingably connected to the respective side frames and the other ends thereof being respectively disposed adjacent the respective bearing devices,

and linkage means connecting the respective deflectable members of the respective bearing devices with the respective said other ends of said levers including lost motion accommodating means for permitting limited deflection of said deflectable members relative to said bolster without transmitting said deflection to the respective levers,

whereby, said side bearing devices oppose roll tendencies up to the deflection of said deflectable members, and greater roll tendencies are opposed by the bolster deflection being restrained to vertical movement only.

5. The improvement set forth in claim 4 wherein:

said bearing devices each further comprise a resiliently compressible eiastomer element interposed between the respective defiectable members and the bolster.

6. The improvement set forth in claim 4 wherein:

said linkage means each comprise a swing arm swingably connected to the side frame adjacent same that is in turn connected to the lever said other end adjacent same by a link,

said lost motion accommodating means comprising pin and slot connecting means between the respective deflectable members and the respective swing arms.

7. In a railroad car truck including spaced side frames between which wheeled axles are journaled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including:

a pair of constant contact resilient side bearing devices are carried by the bolster, one on either side of its said midportion,

said side bearing device each comprise a receptacle mounted on the bolster,

a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces,

with the element bottom surface resting in the receptacle,

and a bearing plate engaging the top surface of the element,

said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate,

said bearing plate defining an upper wear surface adapted to be engaged by the car body bolster,

said bearing plate of each side bearing device extending crosswise of the bolster,

and linkage means interconnected between said frames, said bolster midportion, and both ends of the respective bearing plates on either side of the bolster for translating rolling tendencies applies to said side bearing plates above those short of causing complete deflection of said bearing plates into vertical movement of the bolster by applying the downward acting forces involved to the bolster midportion.

8. In a railroad car truck including spaced side frames between which wheeled axles are journaled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including:

a pair of constant contact resilient side bearing devices carried by the bolster, one on either side of its said midportron,

said side bearing devices each comprising:

a receptacle mounted on the bolster,

a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces,

with the element bottom surface resting in the receptacle,

and a bearing plate engaging the top surface of the element,

said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate, I

with said elements respectively being spaced from the sid walls of their respective receptacles and being free from restraint about their side walls,

said bearing plate being adapted to be engaged by the car body bolster,

said elements being substantially barrel shaped in configuration in vertical cross section transversely and longitu: dinally of the bolster, and being of cross-sectional configuration in horizontal section that is substantially rectangular,

said elements being oriented relative to the bolster such that the long dimension of said horizontal section thereof extends longitudinally of the bolster.

9. A constant contact resilient side bearing device for application to railroad car truck bolsters, said device comprising:

a receptacle adapted to be mounted on the bolster,

a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces,

with the element bottom surface resting in the receptacle,

and a bearing plate for engaging the top surface of the element,

said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate,

with said element being spaced from the side wall of the receptacle and being free from restraint about its side walls,

said bearing plate being adapted to be engaged by the car body bolster,

said element being substantially barrel shaped in configuration in vertical cross section transversely and longitudinally of the bolster, and being of cross-sectional configuration in horizontal section that is substantially rectangular,

said receptacle being formed for application to the bolster such that the long dimension of said horizontal section of said element extends longitudinally of the bolster.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTEON Patent: No- 3.653.3 31 Date Avril 4, i972 Inventofls) Osvaldo F. Chierici It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:-

Column 6, line 64, between said and "frames" insert side Column 6, line 67, for "applies" read applied Signed and sealed this 18th day of July 1 972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM po-mso (10-69) uscoMM-oc 6O376-P69 U.S. GOVERNMENT PRINT NG OFFICE: 1969 0-366-334 

1. In a railroad car truck including spaced side frames between which wheeled axles are journalled and, a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including: a pair of constant contact resilient side bearing devices carried by the bolster, one on either side of its said midportion, with one of said devices being disposed adjacent one of said side frames and the other of said devices being disposed adjacent the other of said side frames, each of said devices including a vertically deflectable member and an elastomeric element interposed between same and said bolster, for resiliently opposing vertical deflection of the respective deflectable members, and linkage means interconnected between said side frames, said midportion of said bolster, and said side bearings for translating rolling tendencies applied to said side bearings into vertical movement of said bolster achieved through downward forces applied to said bolster at said bolster midportion.
 2. In a railroad car truck adapted to support a railroad car body, said truck having first and second side frames in parallel, spaced-apart relation, and a laterally disposed bolster resiliently supported at its respective ends on said side frames, the combination of a resiliently compressible side bearing member secured to said bolster adjacent the first side frame, and including a resiliently supported movable element adapted to support a portion of the weight of the car body, a lever arm having one end thereof connected to said movable element by a vertical motion transmitting linkage and extending from adjacent said movable element to the second side frame and pivotally secured to said second side frame, a second resiliently compressible side bearing and corresponding resiliently supported movable element secured to said bolster adjacent the second side frame, and a second lever arm having one end thereof connected to the second mentioned movable element by a second vertical motion transmitting linkage and extending from adjacent the latter movable element to the first side frame and pivotally secured to said first side frame, and including means for swingably securing said lever arms in scissors-like relation to the midportion of the bolster, said means including means to accommodate free vertical movement of said bolster with respect to said side frames.
 3. In a railroad car truck including spaced side frames between which wheeled axles are journalled, and a bolster member extending between and resiliently supported by the respective side frames, said bolster member being formed at its midportion for pivotal connection to a railroad car body, the improvement wherein: a resiliently flexible side bearing device is mounted on either side of said midportion of said bolster member, said side bearing devices including a bearing plate seated on a resilient body with said body being proportioned to maintain said bearing plate in constant contact with the car body when the car body is carried by the truck, a pair of scissors arms swingably connected together and to the bolster at said midportion thereof intermediate their ends, by lost motion connections and having like ends of each swingably secured to the respective side frames and the other ends of each secured through lost motion connection means to the bearing plate of the respective side bearings adjacent same, said lost motion connection means permitting closure of said side bearing devices on vertical movement of the car body prior to actuating said scissors arms, whereby on closure of said side bearings said scissors arms are actuated to permit only vertical movement of said bolster member.
 4. In a railroad car truck including spaced side frames between which wheeled axles are journalled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including: a pair of constant contact resilient side bearing devices are carried by the bolster, one on either side of its said midportion, with one of said devices being disposed adjacent one of said side frames and the other of said devices being disposed adjacent the other of said side frames, each of said devices including a vertically deflectable member, a pair of scissors levers swingably connected together and to the bolster at its said midportion, with like ends of the respective levers being respectively swingably connected to the respective side frames and the other ends thereof being respectively disposed adjacent the respective bearing devices, and linkage means connecting the respective deflectable members of the respective bearing devices with the respective said other ends of said levers including lost motion accommodating means for permitting limited deflection of said deflectable members relative to said bolster without transmitting said deflection to the respective levers, whereby, said side bearing devices oppose roll tendencies up to the deflection of said deflectable members, and greater roll tendencies are opposed by the bolster deflection being restrained to vertical movement only.
 5. The improvement set forth in claim 4 wherein: said bearing devices each further comprise a resiliently compressible elastomer element interposed between the respective deflectable members and the bolster.
 6. The improvement set forth in claim 4 wherein: said linkage means each comprise a swing arm swingably connected to the side frame adjacent same that is in turn connected to the lever said other end adjacent same by a link, said lost motion accommodating means comprising pin and slot connecting means between the respective deflectable members and the respective swing arms.
 7. In a railroad car truck including spaced side frames between which wheeled axles are journaled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including: a pair of constant contact resilient side bearing devices are carried by the bolster, one on either side of its said midportion, said side bearing device each comprise a receptacle mounted on the bolster, a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces, with the element bottom surface resting in the receptacle, and a bearing plate engaging the top surface of the element, said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate, said bearing plate defining an upper wear surface adapted to be engaged by the car body bolster, said bearing plate of each side bearing device extending crosswise of the bolster, and linkage means interconnected between said frames, said bolster midportion, and both ends of the respective bearing plates on either side of the bolster for translating rolling tendencies applies to said side bearing plates above those short of causing complete deflection of said bearing plates into vertical movement of the bolster by applying the downward acting forces involved to the bolster midportion.
 8. In a railroad car truck including spaced side frames between which wheeled axles are journaled and a bolster extending between and resiliently supported by the respective side frames, said bolster being formed at its midportion for pivotal connection to a railroad car body, the improvement including: a pair of constant contact resilient side bearing devices carried by the bolster, one on either side of its said midportion, said side bearing devices each comprising: a receptacle mounted on the bolster, a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces, with the element bottom surface resting in the receptacle, and a bearing plate engaging the top surface of the element, said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate, with said elements respectively being spaced from the side walls of their respective receptacles and being free from restraint about their side walls, said bearing plate being adapted to be engaged by the car body bolster, said elements being substantially barrel shaped in configuration in vertical cross section transversely and longitudinally of the bolster, and being of cross-sectional configuration in horizontal section that is substantially rectangular, said elements being oriented relative to the bolster such that the long dimension of said horizontal section thereof extends longitudinally of the bolster.
 9. A constant contact resilient side bearing device for application to railroad car truck bolsters, said device comprising: a receptacle adapted to be mounted on the bolster, a resilient elastomer element positioned in the receptacle and formed to define substantially planar top and bottom surfaces, with the element bottom surface resting in the receptacle, and a bearing plate for engaging the top surface of the element, said receptacle defining a side wall thereabout which is spaced below said bearing plate to permit vertical deflection of said bearing plate, with said element being spaced from the side wall of the receptacle and being free from restraint about its side walls, said bearing plate being adapted to be engaged by the car body bolster, said element being substantially barrel shaped in configuration in vertical cross section transversely and longitudinally of the bolster, and being of cross-sectional configuration in horizontal section that is substantially rectangular, said receptacle being formed for application to the bolster such that the long dimension of said horizontal section of said element extends longitudinally of the bolster. 